Joseph t



inarrnn sTaTns 'PATENT OFFICE.

JOSEPH T. MARTIN, or NEW YORK, N. Y.

FLOATING DRY-DOCK.

Specification of Letters Patent No. 1,518, dated March 19, 1840.

To all whom 'it may concern Be it known that I, JOSEPH T. MARTIN, of the city, county, and State of New York, have invented a new and useful Improvement in Floating Dry-Docks, of which the following is a full and an exact description.

The floating dry dock is intended to raise vessels for the purpose of repair; it is composed of several rectangular sections or floating platforms; their number varying according to their size and the weight to be raised, and united together by means herein afterward described. These sections are alike in form and size.

The body of each section is a hollow rectangular parallelopiped or ioat, say, fifty feet long, twenty feet wide, and five feet deep, more or less, constructed of strong timbers, with all its sides, the top not excepted, impervious to water; or is composed of several hollow vessels, each water-tight, and all firmly united together, so as to form a float of the size just mentioned.

In the accompanying drawing of a section, this float is represented as consisting of two hollow rectangular vessels, each, say, twenty-live feet long, twenty feet Wide and five feet deep, more or less, similarly constructed and connected lengthwise; when reference shall be hereafter made to this part of the section the said formation will be presumed.

In order to secure the stability of the flood it is incased within a framework, to which it is firmly bolted. The bottom of this framework consists of cross-beams, each about one foot in breadth and depth, and upon these at right angles the hollow vessels rest.

Figure l, represents the side view of a section, a, a, a', c6', a, a., being ythe ends of the said cross-beams. Two of these beams, a a are at the middle o-f the section, about one foot apart, the rest being distant from each other eight feet, more or less; their extremities are secured by joints and bolts to posts, Ab, Z), Z), b, ZJ, of the same breadth, and, say, half the thickness. The posts are of sufiicient height as to admit of their being similarly secured to the extremities of crossbeams, c, c, c', c, c, c, laid across the top of the float at right angles to the posts. Between the posts, b, &c., and the float, A, A, A, is a distance sufficient to admit a longitudinal beam, B, B, say, twelve inches broad and eighteen inchesvdeep; this beam (and, be it observed, that the framework on both sides of the section is similarly and equally constructed) rests upon the crossbeams, a, a, &c., to which and also to the posts, b, Z), &c., it isjconnected by bolts. Upon this beam, B B, a truss C C rests, suitably fastened by joints yand bolts, and

strengthened by a Vking post I), which will be opposite the middle of the float, or the juncture of the hollow vessels. The timbers composing` the truss` will be of the same breadth with the longitudinal beam, and

about the same depth; to the said timbers all the adjacent posts are bolted. This truss supports another longitudinal beam or string piece E E, of ,the same breadth and depth with that of the lower B B; it is of the same length as the float A A A, and made fast with bolts to the posts andupper cross-beams, c, c, &c.; its upper surface being on a level with the upper surface of the flo-at, and thus regulating the height of the truss C C. Besides being connected by the posts and cross-beams, the sides of 'the framework are more firmly bound together by braces Q Q Q Q, &c., laid across the float, between the cross-beams, and fastened with bolts to the longitudinal beams.

The iooring or deck, (Z d, is formed of plank resting on the cross-beams, but isleft open over the space, e, between the two central ones, c', c. Across this space the keelblocks, F, F, F, are laid, and made fast with 'l bolts to the central cross-beamsupon which they rest. There are several keel-blocks on each section, say, one near each'end of the central cross-beams, and a third over the dinal beams, E E, B B, that lie along the sides of the float, so that their outer surfaces are, or are nearly, in the same plane with the outer surfaces of the longitudinal beams.

These posts are, consequently, inserted at the outer corners of the upper beams or stringpieces, E E, E E.' But the lower beams, B B, project beyond the posts, f f, f f, and of `course beyond the ends of the float A A, each, say, siX feet, more or less. Into the corners of the lower longitudinalbeams B B, j 'A `tops of the corner-posts are also nfirmly bound to "each other by longitudinal and cross-beams, y', j, z', i; andvone or more additional cross-beams, 76,73, bind together the posts g g, g g, at eachrend of the section. At the distance of, say, three Vfeet from each postat theicorner of the float, ano-ther post, Z Z, may be erected, of the same dimensions with the corner-posts@V g', Vand fixed to the longitudinalbeams exactlyin the sanie'manner; Vthese posts Vare for the purpose of.

strengthening the framework at the ends of the section, which framework thus also comtwenty-five degrees.

poses part of the framework of the float.'` This part of the Vframe is stillfurther secured by means of timbers, H H, H H, brac! ing together the endposts g g, g g, and the longitudinal beams of the float frame-work, close to which beams the braces are laid, and made fast with bolts. ',They are bolted, moreover, to all the timbers along which they pass, and to the posts of the iioat, b, through which they are mortised. Above these braces there are others, I, I, extending from a' point near theV centerof the former to the' outer posts g g, g g. The lower braces `make an angle of, say, twenty degrees'with the longitudinal beams, and are joined to the end posts at the height"of,`say, nine feet. The upper braces are joinedI to theA end Vposts. at the height of, say, eighteen feet, and tojthelower braces at an angle of, say, It is only meant to specify the fact that the parts'just mentioned are firmly bound together, as the manner may be varied. y

It has been already stated that the four extreme posts, g g, f j", Figs. l and 2, at each y end of the section, are the corner posts of ak frame-work for the reception of an addi.- tional vessel or end-float, so called tondis` tinguish it from the main orA body iioat.

The endfloats,` R R, R R, Fig. 2, or S, Fig. 3, are -hollow rectangular vessels built of strong timbers according to their size, and impervious to water on` all sides, the tops not excepted :r they are entirely sep'- arate, and movable vertically within the framework. Their breadth, measured with the breadth of the main float, is suchjthatA they rest, when lowered, upon the'low'er longitudinal beams B, B,Figs. 2 andy B, y but is somewhat less than the entire breadth f of the frame; andvtheir depth is such that their upper surface,when lowered, is, or is Vframework,and between the posts, m, m, on which the side rollers run, another post,

nearly, inwthe same plane with the deck.

Twoposts, m, a, are secured within each corner of the end-float frames, close or near to the corner posts of said frames, each presenting an interior surface, twelve inches broad, more or less, at right` angles to each determined, the length` and breadth of the end-floats. To each ofthe four posts, a, e, a, a, on whichthe end rollers run, and p to the sides onV which they run, metal racks,

y, thy, y, are fastened, but'so as not to interfere with the rollers; pawls, 2, 2, 2, 2, are ,fixed on the tops of the end-fioats, opposite Vtothe racksgand by means of these pawls the 'end-floats, when 4depressed into the water, are retained at any desirable depth.

Accordingto the dimensions herein specified, the length of the end-floats isfless than theobreadth, but their length is indefinite, and the greater it is, the greater will be the buoyant power of the section. The length of their side framework varies with the length of the end-floats.

To each of the sides ofthe end-float N, `is firmly secured; and to each of these posts a rack, 3, is fixed, along which a cog-` wheel, 4, runs as afterward described. The

teeth of these racks are, or are nearly, in a line `equidistant fromV the two nearest corner-posts, g g, f f; andtheir surface is, likethe surfaces of theracks already mentioned, parallel to the ends of the section. On or near the central part of the top of each end-float, a lwinchis xed, at a `convenient height and ofany suitable gearing. Inthe accompanying `drawing this' winch, Uconsists of two -'cov"g`wheels,'the smallerv givingl motion tothe larger. The axis, 5, 5, of the larger cog-wheel is extended and supported Vbygudgeons,.6,"`6, fastened tothe topo-fthe end-float. .On the ends of this axis smallIcog-wheels, 4, 4,. areiixed, and

revolve with the said axis on the racks last ness, is fixed to the deck at "each end. The

YA stoutV rect' ngular frame or stand, the corner'posts'v of which, K, K', K, `K, are, say, each twelve inches in breadth and thickends of these stands are parallel to the ends of the deck, at the distance of twelve inches, more or less; and their sides are distant from the sides of the deck, four feet, more or less. Their height is, say, live feet, and should not be less than the depth of water drawn by the vessels which are proposed to be raised upon the dock. The length of the stands is nine feet, more or less, but this length is indeterminate, and in no fixed proportion to their breadth. These stands are for the support of retangular reservoirs, J, J, the corners of which rest upon, or are near to, the corner-posts of said stands. Should the said cornerposts not rest upon the cross-beams on which the deck is laid, additional cross-beams P, P, should be laid on the float, in a line with and directly under the said corner-posts; and to these cross-beams the stands are firmly bolted. The reservoirs, J, J, are built of strong timbers2 and secured to their stands with dogs or bolts, u, u. Their height is, say, seventeen feet, or such that the capacity of each shall be equal to, say, from one-fourth to one-third the capacity of the main-float, A A A.

The reservoirs, J, J are filled by means of pumps fixed Within them, and worked by perso-ns standing on the yboards that cover the said reservoirs. In the accompanying drawing there are two pumps, a', z, Fig. in each reservoir, the diameters of which are, say, four feet apart, and equidistant from, or close to, one end of the reservoirsayJ the end of the reservoir farthest distant from the center of the sect-ion, as in Fig. 4,-or they may be thus situated at any side of the reservoir, so that the pipes, e', a, which feed the pumps, do not interfere with the lever, B B, Fig. 2, which moves the coupling-timbers, as afterward explained. Their piston-rods, fn, u, Fig. 3, project equally to a convenient height above the cover of the reservoir; a bar, 79 p, with hinge joints connects the ends of the piston-rods, to the center of which another bar, o o, Fig. 4, is fixed at right angles. This bar, 0 o, is the fulcrum to any part of which the lever or handle is fixed to work the pumps, and is supported by suitable props or gudgeons, Q, g', Figs. 1, 3 and 4; one end of the fulcrum, 0 0, projects beyond the end of the reservoir, the gudgeon, g, which supports this end, resting on a board which also projects beyond the end of the reservoir, as in Fig. 4; at this end of the fulcrum, within the gudgeons, a heavy pendulum, r, Figs. 1, 3 and 4, is attached, which moves as near as may be to the end of the reservoir, and serves to aid and regulate the action of the pumps.

.The pumps are fed by pipes, e e, Fig. 3, which are led perpendicularly through the bottom of the reservoir, the deckv and the' top of the main-float, into a small cistern, that is xed within the main-float, directly under the pumps; all its sides, the top not excepted, beingimpervious to water. i From this cistern, an-air-pipe, s, is led in any manner to the top of the reservoir. Another pipe, t, Figs. l and 3, which feeds the cistern, is led fromits interior through the side of the main float at any convenient point, say, aboveand close to the lower longitudinal beam, B. A perpendicular rod, u, accessible with the hand from the top of the reservo-ir, lies along the outside of the reservoir, passing through the deck and` top of the float, in the direction of the inletpipe, t, and serves as the handle ofav cock or sluice-gate that is fixed in the said pipe` at this point; this cock or sluice-gate is used to stop the ingress of the water and enable all the water to be pumped out of the cis-y tern; it is called the cistern-cock or sluicegate. Another pipe, e, Fig. l, leads from the interior of the cistern to the interior of .as the rod or handle, u, already described.

Vhen the cistern-cock is shut and the floatcock open, the leakage of the main lio-at, if any there be, can be pumped out; the float cock is never opened except for this purpose.

The cisterns are'each as small as may be; but of a size sufficient to admit the pipes described, and to admit a volume of water sufficient to feed the pipes connected with the pumps. All the aforesaid pipes, where they pass through the timbers of the main float, the reservoirs, or the cisterns, are to be fitted into the said timbers so tightly that the said 'reservoirsJ cisterns, or main-float, may be each separately still impervious to water as hitherto described, excepting through the said pipes as already explained. No water, leakage excepted, is ever inside J[he main-float. To let the water out of the reservoirs, there is an opening, n, Fig. 3, at the bottom of each, at any convenient point, covered by a valve or gate.; and to the said valve or gate there is a rod or ropeJ d, el, fixed, stretching to a point accessible with the hand from the top of the reservoir, and serving to open the said valve or gate.

To let the water out of the end-float, there is an opening, G, at the bottom of each, at any convenient point, into which a cock `is inserted; this cock is opened or shut by a rod, t, stretching to a point accessiblev with the hand from the top of the end-float. I'If the said rod be fixedV within the end-float it must pass through the' timbers of the endfioat, in such a manner that it may be still imperviousto` water, as hitherto described.

Alon-g the deck at an. equal distance from iso - seven feet from the end of the deck, these Y bolts.

stanchions are above the longitudinal beams, E E, B B, of the float frame work, mortised through both, and through the truss timber, C vC, if necessary,V and secured with At the `height'of, say, eightinches above the deck, they are'bound together by l a timber or tiet-piece, secured byjoints and v deck and between the stanchions and tie-V Y a horizontal joint fixed to the deck.

bolts; thus leaving an opening, w, above the piece.V To tie thev sections together, a coupling-timber, T` T,VV runs through each of these openings into thesimilar opening of the next section g; the openings on the adjacent sides of thesections being exactly opposite, each to each.V They said couplingtimbers are not so large asfto prevent their being easilyv pushed withinthe openings: their breadth is as near the breadth of the openings as may be, to keepf the sections from moving from each other in a lateral direc-l tion, but their depth is` as much less than the height of the openings, m, as will suffer. the deck of any one section to settle a few inches lower, if necessary, than the deck of i the section adjacent. When the adjacent sides of the sections exactly coincide, the

coupling-timbers are at right angles to thev plane of contact, and extendfrom the stanchions to an equal distance on the deck of each adjacent section, say, eightfeet, more or less; at the .distance of, say, two feet from each end, the said coupling timbers being secured Vin a direction atright angles to the side of the deck by iron bands or by bolts, y, y, y, y, Fig. 2, projecting from the deck on each side of, and close to, the said coupling-timbers In the direction just mentioned each may be moved by a lever of the secondv order B B, theffulcrum of which is There is a lever of'thiskind at both ends of each coupling-timber; one on one section, and the other on the section adjacent.. The lever is not jointed tothe couplingftimber, but passes through an iron band or between two bolts, fait, fastened to its end. The handle of the lever projects toward the nearest end-fioat, but does not touchit; to its endv two ropes are attached which run separately through tackle-blocks just xed to the extreme cornerposts of the reservoir-stand, or to the deck, asfmay be judged most convenient. These ropes may be pulled, and, consequently, the sections 4may be farther separated or `brought nearerjjeach other, byV per` sons standing on the topof theend-float:

Projecting above the deckv blocks.

It may be well here to repeat, what has' been already said in substance, that the entire machinery of each section, on each side of the open space, e, between the-central beams, Figs. land 2, is exactly similar and equal. The floating/dry-dockjis formed by uniting the sections as above described. j VTo raise a vessel the dock is sunk, so far Vthat vthevessel mayfioat above the keelblocks. To'effectfthis theendoats are depressed as low as possible, and water is pumped into the reservoirs simultaneously and equally. rllhe weight of this water causes the dock to sink; and, the cocks of the end-fioat being open,the said end-f1oats fill with waterfin proportion to the sink` ing of the dock. `As soon4 as the end-oats are full, or as soonv as they contain so much water as may be judged sufficient, they are raised above the water by the means herein already described, water continuing to be pumped into the reservoirs until `the dock settles at the depth` required. The vessel is then floated over the keel-blocks, and the bilgeblocksl brought tobear, as much water `being allowed to escape from the reservoirs or end-floats, as may be necessary in order to eect anequal pressure of thebottom of:

the vessel upon all the keel-blocks and bilge- The reservoir-cocks or sluice-gates, which are all ofjan equalaperture, are then simultaneously opened, andthe water allowed to escape. The endefloats are emptied in the same manner, and at the same time; as soon as empty, their cocks are shut, and they are forced downward into the water, simultaneously and equally, by the machinery already described, as far as the said ma- Y chinery willpermit.` For furtherrsecurity, thevessel may be then shored `in the usual way.` From this description it is plan that the distance between the reservoirs of each section, `limits the size of the vessels to be raised bythe dock, as far as the breadth of the vessels is concerned. i

vA dock formed of four sections, each of the numeral dimensions herein specied,will

be suitable forraising vessels, the registered burden ofwhich does not exceedthree hundred tons. But, by increasing thelength of themainLfloat, and the other parts vin proportion to said increase, adock may be con-` structed to receive vesselsof the largest size.`

Perhaps, in this case, a variationin the manner of constructing the v-frame-work might be necessary, but this difference any carpenter will `be able to idetermine from the iso specifications herein set forth. It is also plain, that, with the same length of mainiioat, the power and buoyancy of each seotion may be illimitably increased by increasing the length of the end-floats; the increased weight of the timbers comprising the said end-floats, and the increased weight of the water within them, at the same time materially helping to sink the dock, whenever it may be required. In fact the size of the end-floats may be such that the weight of them alone, and of the water Within them, would be sufficient to sink the dock, Without the aid of the reservoirs. Hence, the size of the reservoirs may be diminished in proportion to the increased capacity of the endloats. In this case also, a variation of the manner may be necessary in constructing the end-float framework, but this variation any carpenter will readily determine. yIt may also be stated that two or more end-floats may be advantageously constructed at each end of thesection.

I do not claim as my invention the formation of a floating dry dock by the union of sections or floating platforms. I claim as my invention the construction and use of end-floats, or any of the separate parts of the above-described floating dry-dock. But the end-floats heretofore in use have had no machinery attached to them by which they might be filled with water, when necessary, for the purpose of causing to sink, or of aiding to sink, the oating dry dock; and have in fact been so constructed with the intention that no watershould ever be admitted Within them; and

Therefore, I do claim as my invention and wish to secure by Letters Patent- 1. The new and useful improvement, hereinbefore fully described, or any other method substantiallyv the same, by which they are filled with water and emptied of the same for the purposes herein set forth.

2. In combination with this, I do further claim the application of racks and pawls for securing the position of the end-floats, as A herein set forth.

3. I do also claim the above described combination of machinery, or any other substantially the same, by which the dock is lengthened or shortened while the deck is 

